Water is a very important resource in our life . The availability of water resources on earth are limited and unevenly distributed. Human demand for water has been growing for two reasons. The available water is to be conserved. This module explains the major practices adopted in water conservation.
2. 1. Importance of water and Water
Conservation:
Water is a very important resource in our life .
The availability of water resources on earth are
limited and unevenly distributed. Human
demand for water has been growing for two
reasons. Firstly, the growth of the human
population.
3. Secondly, as the human standards of living
improve in the various countries of the world
the demand for water also increases to meet
new needs in industry, agriculture and
domestic use.
Water is becoming scarce due to increase in
Population, industries and agricultural activities
and due to poor rainfall. Water conservation
depends on our wise use of these resources.
4. What is water conservation?
Water conservation includes all the policies,
strategies and activities made to sustainably
manage the natural resource fresh water, to
protect the water environment, and to meet
the current and future human demand.
Population, household size, and growth and
affluence all affect how much water is used.
5. Some ancient Indian methods of water
conservation: A large number of tanks were
cut in the rocks to provide drinking water.
Each fort in the area had its own water
harvesting and storage system in the form of
rock-cut cisterns, ponds, tanks and wells.
Underground baked earthen pipes and tunnels
to maintain the flow of water and to transport
it to distant places. Bamboo Drip Irrigation.
6. Rainwater harvesting -In urban areas, the
construction of houses, footpaths and roads
has left little exposed earth for water to soak
in. Rainwater harvesting essentially means
collecting rainwater on the roofs of building
and storing it underground for later use.
7. Some of the benefits of rainwater harvesting
are as follows:
Increases water availability/ Checks the
declining water table
Is environmentally friendly?
Improves the quality of groundwater through
the dilution of fluoride, nitrate, and salinity ?
Prevents soil erosion and flooding especially in
urban areas.
8. Agriculture:
Conservation of water in the agricultural sector
is essential since water is necessary for the
growth of plants and crops. A depleting water
table and a rise in salinity due to overuse of
chemical fertilizers and pesticides has made
matters serious. Various methods of water
harvesting and recharging have been and are
being applied all over the world to tackle the
problem.
9. Reducing water demand: Simple techniques
can be used to reduce the demand for water.
The underlying principle is that only part of the
rainfall or irrigation water is taken up by plants,
the rest percolates into the deep groundwater,
or is lost by evaporation from the surface.
Therefore, by improving the efficiency of water
use, and by reducing its loss due to
evaporation, we can reduce water demand.
10. The goals of water conservation efforts
include:
1. Ensuring availability of water for
future generations.
2. Energy conservation as water
pumping, delivery and wastewater treatment
facilities consume a significant amount of
energy.
11. In some regions of the world over 15% of total
electricity consumption is devoted to water
management.
3. Habitat conservation where
minimizing human water use.
4. Household applications- Reducing
Domestic Water use - Some strategies for
reducing domestic consumption include:
5. Replace lawns in semiarid and arid
urban areas with xeriscaped surfaces.
12. 6. Encourage the use of efficient
irrigation systems for home garden and lawn
use.
7. Manufacture and use of more
efficient dishwashers, washing machines, and
bathroom showers and toilets.
8. Encourage leak detection and repair
for distribution systems.
9. Education can encourage people to
reduce the amount of personal consumption.
13. Practices for Residential Users= Engineering
Practices- Plumbing, Low-flow plumbing
fixtures, Low-Flush Toilets, Low-Flow
Showerheads.
Gray Water Use. Domestic wastewater
composed of wash water from kitchen sinks
and tubs, clothes washers, and laundry tubs is
called gray water.
14. Landscaping-Lawn and landscape maintenance
often requires large amounts of water.
Landscape Irrigation. Xeriscape landscaping
uses all of the following: planning and design,
soil analysis, selection of suitable plants,
practical turf areas.
15. Behavioral Practices- Water can be saved in
the bathroom, Water can be saved in the
laundry room, Outdoor water use can be
reduced by watering the lawn early in the
morning or late in the evening.
10. Practices for Agricultural Users -Water-
saving irrigation practices, Agricultural
applications (Reducing Agricultural water use)-
The cultivation of food crops that require less
water for growth.
16. 11. The use of lined or covered irrigation
canals to reduce infiltration and evaporation
losses. * Irrigating crops at night or early
morning when evaporation potentials are
low.)
12. Practices for Industrial/Commercial Users
=Water Reuse and Recycling. Identification of
water reuse opportunities.
17. 13. Commercial applications- Reducing
Industrial Water use - Industry is the second
largest user of water supplies. Reducing the
amount of water used in industry. * Designing
industrial processes to recycle water. *
Increasing the cost of water to industries to
encourage water recycling. * Recycling
materials themselves can also greatly reduce
water demand.
18. 14. Water Reuse. Water Reuse- Public
education programs.
2. WATER CONSERVATION TECHNIQUES:
A number of techniques and technologies can
be used to make agricultural, industrial and
domestic water use more efficient.
19. How to Conserve Water and Use It Effectively:
Water users can be divided into two basic
groups: system users (such as residential users,
industries, and farmers) and system operators
(such as municipalities, state and local
governments, and privately owned suppliers).
20. Water use efficiency practices are:
1. Engineering practices: practices based on
modifications in plumbing, fixtures, or water
supply operating procedures.
2. Behavioral practices: practices based on
changing water use habits. Practices for
System Operators-Engineering Practices-
Metering, Leak Detection and repair.
21. Water conservation = Recycling, reuse,
wasteland reclamation, use of decision support
systems in watershed management.
Crop water Planning with special reference to
different agro-ecological zones.
Drought management = causes and impacts,
short term and long terms strategic measures
to counter vulnerability due to drought.
22. Storm water and flood management,
management of water quality .
Storm water management, design of drainage
system.
Urban flood damage due to changing land use
pattern. Sources and types of pollution, case
study from a watershed which has experienced
rapidly industrialization.
23. Redistribution of water- canals:
By arranging supply of water from areas having
lesser demand to the areas having greater
demand, water crisis can be minimized. By
construction of surface water reservoirs and
storage of excess water in them, supply can be
made to scarcity affected areas.
24. Redistribution of water is also possible through
canal system.
Canal system transfers water from excess rain
water areas to scarce rain water areas and
conserves water for different uses.
25. RATIONAL USE OF GROUNDWATER:
Groundwater meets 25 per cent of total supply
of water in the world, remaining 75 per cent
supply is met by surface water sources of
rivers, lakes etc.
Demand for groundwater goes on increasing in
proportion to its available quantity due to
which quantity of groundwater goes on
decreasing.
26. The groundwater exploitation should be only in
proportion to its recharging capacity.
USE OF MODERN IRRIGATION METHODS:
In drip irrigation method, pipes with holes are
spread over the surface of land so that the crop
directly receives water. There is no loss due to
evaporation in this system and almost 95 per
cent water is utilized.
27. INCREASING FOREST COVER:
As per to hydrological movements, water is
received through rainfall every year m different
quantities on the surface of the earth. This
water flows on the surface and reaches the
seas.
28. Some part of rainwater is stored in stable
water reservoirs (lakes and tanks), whereas
some quantity of water infiltrates into the land
and takes the form of groundwater.
CHANGE IN CROP PATTERN:
Excess water is not required if crops are grown
according to agro-climatic conditions but in the
present race of development, changing crop
pattern with higher profits has replaced them.
29. These commercial crops require more water
than the traditional crops.
FLOOD MANAGEMENT:
A large portion of fresh water in the world
becomes devastating due to floods. By
construction of embankments and canals a
large part of land can be conserved besides
minimizing flood losses.
30. Intensive afforestation can also provide
security from floods. If will be helpful in
absorption of water in the soil.
REUSE OF URBAN WASTE WATER:
Demand for water has increased in cities due
to increasing urbanization. There is no
provision for waste water treatment in many
big towns and cities of various countries of the
world.
31. After use of water in urban areas, disposed
waste water can be treated and conserved for
use in agriculture in the peripheral areas of
cities.
Drought Tolerant Crops and Seeds:
Grow the right crop for the growing region.
Regions which suffer water shortages are wise
to plant crops which are more tolerant to
drought.
32. Drought tolerant crop seeds are available both
through biotechnology and from native seed
varieties. Drought tolerant seeds available
today include corn, rice, and cotton.
Ripper-Furrower Planting System: Tractors are
used the first year to start the ripped furrow
system. After the first year, farmers plant crops
directly into the rip lines using an animal drawn
direct seeder.
33. 3. WATER EROSION PROCESSES:
Factors affecting erosion, Types of erosion.
Assessment of erosion, modelling erosion using
USLE, RUSLE. Control measures for soil erosion
Causes of landslides in watersheds having hilly
terrain.
34. Water Erosion Control Practices:
Reducing runoff velocity(slope management,
waterways, diversion channels, engineering
structures, etc). Strip cropping is a very
effective and inexpensive method for
controlling soil erosion.
35. Strip cropping is a combination of contouring
and crop rotation in which alternate strips of
row crops and soil conserving crops (sods) are
grown on the same slope, perpendicular to the
wind or water flow.
36. DIVERSION:
A diversion is a channel constructed across the
slope with a supporting ridge on the lower side
to divert excess water from one area for use or
safe disposal in other areas.
SEDIMENT BASIN:
This practice is a constructed basin designed to
collect and store waterborne debris or
sediment.
37. STREAMBANK & SHORELINE PROTECTION :
Using vegetation or structural techniques to
stabilize and protect banks of streams, lakes, or
excavated channels against scour and erosion.
STRUCTURE FOR WATER CONTROL:
This practice is a structure that conveys water,
controls the direction or rate of flow, or
maintains a desired water surface elevation.
38. UNDERGROUND OUTLET:
A conduit installed beneath the ground surface
to collect surface water and convey it to a
suitable outlet.
Mulch, a type of protective covering which is in
direct contact with the ground, provides more
protection than canopy cover.
39. Terracing is a combination of contouring and
land shaping in which earth embankments, or
ridges, are designed to intercept runoff water
and channel it to a specific outlet.
Terraces reduce erosion by decreasing the
steepness and length of the hillside slope and
by preventing damage done by surface runoff.
There are basically two types of terraces:
bench terraces/ broad base terraces.
40. The bench terrace, perhaps one of the oldest
forms of terraces, is used to reduce land slope.
The broad base terrace, on the other hand, is
used to control and retain surface water on
sloping land.
Vegetated waterways are built to protect soil
against the erosive forces of concentrated
runoff from sloping lands.
41. By collecting and concentrating overland flow,
waterways absorb the destructive energy
which causes channel erosion and gully
formation.
Waterways can have cross sections in
parabolic, trapezoidal, or triangular form,
depending on the functional requirements.
Several of these requirements are climate,
channel capacity, and desired flow velocity.
42. Grass linings should be hardy, dense - growing
perennials adapted to the geographical region
and soil. The grass should be cut periodically,
fertilized as needed, and not subjected to
prolonged traffic by either livestock or vehicles.
Contouring entails performing all tillage and
planting of crops on or near the same elevation
or "contour."
43. It is applicable on relatively short slopes up to
about 8 percent steepness with fairly stable
soils. By planting across the slope, rather than
up and down a hill, the contour ridges slow or
stop the downhill flow of water. Water is held
in between these contours, thus reducing
water erosion and increasing soil moisture.
44. Strip cropping is a very effective and
inexpensive method for controlling soil erosion.
Strip cropping is a combination
of contouring and crop rotation in which
alternate strips of row crops and soil
conserving crops (sods) are grown on the same
slope, perpendicular to the wind or water flow.
45. When soil is detached from the row crops by
the forces of wind or water, the dense soil
conserving crops trap some of the soil particles
and reduce wind translation and/or runoff.
Land Use and Management Practice: Select
appropriate land use/ Maintain organic matter/
Maintain crop residue cover/ Reduce tillage/
Use zero tillage or direct seeding/ Use
conservation fallow/
46. Grow forages and use crop rotations/ Use
direct seeding for pasture conversion/
Controlling Severe Erosion: Grassed
waterways/ Lined channels/ Terracing/
47. 4. WATER RESOURCES IN WATERSHEDS
AND RIVER BASINS:
The watersheds are natural hydrological
entities that cover a specific aerial expanse of
land surface from which the rainfall runoff
flows to a defined drain, channel, stream or
river at any particular point.
48. The terms region, basin, catchment, watershed
etc are widely used to denote hydrological
units.
Size of the watershed is of practical
importance in development programmes. In
deserts and flat terrains with little incipient
drainage, it may be difficult to delineate small
sized watersheds whereas in undulating and
hilly terrains smaller sized watersheds could be
easily delineated.
49. Watershed is considered to be the basic core
for planning and management of water
resources. Since a watershed is bound by
natural drainage pattern, optimum utilization
of natural resources including water must cater
to the needs of the complex interactions
between the various parts of the watershed.
50. Sr. NoType of Watershed Area Covered
1 Micro Watershed 0 to 10 ha
2 Small Watershed 10 to 40 ha
3 Mini Watershed 40 to 200 ha
4 Sub Watershed 200 to 400 ha
5 Macro Watershed 400 to 1000 ha
6 River basin above 1000 ha
51. Concept of watershed and river basin,
characteristics of watershed behavior, effects
of land use changes.
Land capability and suitability classification,
watershed development.
52. Integrated river basin management:
Strategic planning of water resources
development, prioritise limited resources,
managing irrigation, industrial and drinking
water demands, protection of sensitive water
bodies, riparian areas. Water policing for
pollution load, discharge and withdrawal
controls at different river sections.
53. Management of watersheds as integrated
hydrologic and ecosystem units, with an
integrated approach to groundwater and
surface water, water supply and water quality,
climate change and its impacts on water
resources, managing extreme events of flood
and droughts, integrated urban water
management, and environmental services from
water resources.